SHEEP DIPPING TANKS 



2i'i 



the end of each brick should be dipped in hot tar before laying, and the 

 space between the back of each brick and the excavated hole tamped in 

 with clayey material selected from the ground excavated from the hole. 

 It would, however, be better to use the more expensive hard-burned 

 blue bricks, in which case the tarring operation might be dispensed 

 with. 



The bricks should be thoroughly wetted before being laid. If laid 

 dry, they prevent the mortar from setting hard by absorbing its moisture 

 and drying it out too rapidly. The mortar joints should not exceed 

 three-eighths of an inch in thickness. 



- - - -■•', •■- 



;jms%MRt-. •-< 



Fig. 192. 



Building the Outslope. — In the case of the original tank, experiment 

 demonstrated that the outslope was slightly too steep, therefore in the 

 accompanying plans the outslope has been reduced to a slope of 30 degrees 

 with the horizontal. 



The bottom of the outslope consists of a layer of 1 to 2 to 3 concrete 

 3 inches thick. In the concrete, iron steps are imbedded, consisting 

 of pieces of old tyre iron. The surface of the concrete between the steps 

 is rendered with a £-inch layer of 1 to 2 cement plaster, applied when 

 the rest of tank and outslope is being rendered, and finished with a rough 

 surface. The steps project 1 inch above the surface of the plaster, and 

 are most effective. The six steps above the level of the dipping 

 fluid are perforated with £-inch holes to prevent the retention of fluid 

 above them. 



